[Critical analysis of vascular explorations in diabetic complications]

Diabetes mellitus is the chief medical cause of amputation. The risk of amputation is 15-fold higher in diabetic subjects and 5 out of 6 amputees are diabetic. Among the three risk factors for amputation in diabetic patients-neuropathy, ischemia, and infection-ischemia is the most difficult to quantify. Thus, functional and/or distal foot arteriopathy may be present without any clinical symptoms long before trophic changes occur. Therefore additional vascular explorations, including measurement of systolic toe pressure, must be performed. Physical examination is sufficient to diagnose lower limb arterial disease when ankle pulses are missing, but severe foot ischemia may be present despite minimal clinical signs and normal ankle pulses. Mediacalcinosis alters ankle pressure. Toe pressure is the most reliable test for quantifying ischemia of the diabetic foot. Other investigations such as TcPO(2) measurement, laser-Doppler and capillaroscopy are useful for revealing early functional diabetic microangiopathy, but they can only be done and interpreted in specialized centers.